Consultant, Expert Witness, Electrical & Mechanical Accidents

DESIGNING COST-EFFICIENT MECHANISMS

Minimum Constraint Design (MinCD) provides zero looseness and zero binding with loose tolerances and low cost. For example, with MinCD, the author's company made very large industrial robots using only small machine tools.

This book is the source of the technology.

Table of Contents

Part 1: Minimum Constraint Design (MinCD),Semi-MinCD, and Redundant Constraint Design (RedCD)

Chapter 1 General Description

Chapter 2 Degrees of Constraint

2.1 Disadvantages and Benefits of RedCD

2.1.1 Disadvantages

  • 1. Part to Part Variation
  • 2. Assembly Stresses and Strains
  • 3. Deformation in Normal Service
  • 4. Damage Deformation
  • 5. Thermal Deformation
  • 6. Wear Deformation

2.1.2 Benefits

  • 1. Assembly Deformation
  • 2. Operating Deformation
  • 3. Load Spreading Deformation

2.2 Theory of MinCD

  • 1. Axes
  • 2. Freedoms and Constraints
  • 3. An Example of Pure MinCD
  • 4. Degree of Purity
  • 5. Further Theory
  • 6. Rules and Principles
  • 7. Rotary Constraints
  • 8. Matched Sets
  • 9. Relative Constraint
  • 10. Needed Theory

2.3 Examples of Bad RedCD

  • 1. Three Bearings on One Shaft
  • 2. Dovetail Slides
  • 3. Bolted Feet
  • 4. Lead Screw
  • 5. Chairs and Tables

2.4 Examples of Good RedCD

  • 1. Cylinder Head
  • 2. Flanged Joint and Bolt Circle

2.5 Examples of MinCD

2.5.1 The Ubiquitous Tripod

  • 1. Surveyors' Instrument Tripod
  • 2. One Leg Stool
  • 3. Three Leg Chairs
  • 4. Kettles
  • 5. Ancient Tripods
  • 6. Tension Tripods
  • 7. Tripod Derricks
  • 8. Surface Plates
  • 9. Machine Tools,
  • 10. Jigs and Fixtures
  • 11. Tricycles
  • 12. Trailers
  • 13. Bell Striker

    2.5.2 Examples of MinCD in Industry

    • 1. Lathe Chucks
    • 2. Robot Grippers
    • 3. Straight Line Mechanism
    • 4. Larger Straight Line Mechanism
    • 5. Large Linear Motion Mechanism
    • 6. Large Storage and Retrieval Robot
    • 7. Safety Caging
    • 8. Assembly
    • 9. Tandem Shafts

    2.6 MinCD With Flexible Bodies

    • 1. Long Machine Beds
    • 2. Robot Spar
    • 3. Flexible Cart

    2.6.1 Classes of Flexible Body

    • 1. Thin
    • 2. Long
    • 3. Large

      2.7 Load Dividers

      Chapter 3 Kinds of Constraint

      3.1 Hard Constraints 3.1.1 Examples of Hard Constraints
      • 1. Point and Surface
      • 2. Ball and Surface
      • 3. Roller and Surface
      • 4. Shaft and Sleeve Bearing
      • 5. Ball and Socket
      • 6. Bolted Feet

      3.1.2 Examples of Wheel Constraints

      • 1. Single Narrow Wheel
      • 2. Pair of Wheels Tight on a Common Axle
      • 3. Pair of Wheels Loose on a Common Axle.

      3.1.3 Examples of Wheels on Tracks

      • 1. Two Flanges on One Wheel
      • 2. One Flange on Each Wheel of a Pair
      • 3. Traditional Railroad Wheels
      • 4. V Grooves

      3.1.4 Examples of Rotary Hard Constraints

      • 1. Jaw Clutch
      • 2. Splined Shaft
      • 3. U-Joint
      • 4. Splined Shaft

      3.2 Centering Constraints

      1 Hard Centering, 2. Soft Centering.

      3.3 Human Constraints

      3.4 Soft Constraints 3.4.1 Uses For Soft Constraints

      • 1. Shock and Vibration Isolation
      • 2. Oscillation Damping
      • 3. Contact Stress Reduction
      • 4. Scratch and Dent Prevention
      • 5. Pressure Distribution
      • 6. Over-Travel Cushioning
    • 7. Separation of Sliding Parts

    3.4.2 Seating Forces

    3.4.3 Materials Used in Soft Constraints

    3.4.4 Effects Used in Soft Constraints

    • 1. Elasticity
    • 2. Hysteresis
    • 3. Viscosity
    • 4. Buoyancy
    • 5. Eddy Currents
    • 6. Magnetic Attraction and Repulsion
    • 7. Gravity
    • 8. Fluid Pressure

    3.4.5 Devices Used For Soft Constraint

    • 1. Dashpots
    • 2. Cylinders
    • 3. Motors
    • 4. Voice Coils
    • 5. Clutches and Brakes
    • 6. Shock Mounts

    3.4.6 Inflated Constraint Devices

    • 1. Inflated Seal
    • 2. Air Springs

    3.4.7 Part Grippers

    • 1. Inflated Tube
    • 2. Expanding O-Rings
    • 3. Vacuum Grippers
    • 4. Ventricles
    • 5. Squeeze Valve
    • 6. Air Tube Clutch and Brake
    • 7. Inflatable Actuator

    3.5 Flexible Constraints

    • 1. Flexures
    • 2. Flexible Couplings
    • 3. Torsion Flexures
    • 4. Suspension Flexures
    • 5. Bimetal
    • 6. Tape
    • 7. Electrical Flexures
    • 8. Tension Flexures
    • 9. Hoses
    • 10.Flexible Hose and Cable Supports
    • 11.Energy Storage Flexures
    • 12.Balancing Springs
    • 13.Flexible Containers
    • 14.Musical Instruments
    • 15.Clock Crystals
    • 16.Latches

    3.6 Adjustable Constraints 3.6.1 Reasons for Adjustability

    3.6.2 Adjustable Parameters

    • 1. Straightness
    • 2. Squareness, Levelness, and Plumbness
    • 3. Angle
    • 4. Phase
    • 5. Distance
    • 6. Alignment and Parallelism
    • 7. Force and Pressure
    • 8. Electrical Parameters
    3.6.3 Adjustment Techniques
    • 1. Adjusting Screws
    • 2. Eccentrics
    • 3. Shims
    • 4. Wedges
    • 5. Phasing Hubs
    • 6. Adhesives and Grout
    • 7. Hammers and Files
    • 8. Part Replacement

    3.6.4 Adjustment Measurements

    3.6.5 Geometrical Instruments

    • 1. Level
    • 2. Square
    • 3. Angle Scales
    • 4. Plumb Line
    • 5. Linear Distance Instruments
    • 6. Optical Measuring Systems

    3.6.6 Other Instruments

    • 1. Human Touch, Sight, and Hearing
    • 2. Transducers

    3.7 Variable Constraints

    • 1. Cams
    • 2. Linkages
    • 3. Lead Screws
    • 4. Air Cylinders
    • 5. Hydraulic Cylinders
    • 6. Electric Motors
    • 7. Gears
    • 8. Rack and Pinion
    • 9. Chain, Tape,and Rope
    • 10.Belt and Pulley
    • 11.Servos

    3.8 Friction Constraints

    3.8.1 Friction Devices
    • 1. Collets
    • 2. Chucks and Vises
    • 3. Wedges
    • 4. Taper Pins
    • 5. Setscrews
    • 6. Belt and Pulley
    • 7. Friction Variable Speed Drives

    3.8.2 Screw Thread Retention

    • 1. Plastic Inserts
    • 2. Self Tapping Screws
    • 3. Deformed Threads
    • 4. Tapered Threads
    • 5. Adhesives
    • 6. Lockwashers
    • 7. Locknuts
    3.9 Self-Aligning Elements
    • 1. Caster
    • 2. Single Gimbal
    • 3. Two Gimbals
    • 4. Two Gimbals Alternate
    • 5. Three Gimbals
    • 6. Sliding Gimbals
    • 7. Universal Joints
    • 8. Self-Aligning Linear Ball Bearing
    • 9. Spherical Joint ("Ball Joint")
    • 10.Spherical Bearing Mount
    • 11.Levelling Pads
    • 12.Spherical Washers
    • 13.Self-Aligning Roller Bearing
    • 14.Linear Chained Roller Bearing
    • 15.Ball Caster
    • 16.Spline
    • 17.Active Self-Alignment

    Chapter 4 Beneficial Non-MinCD

    4.1 Semi-MinCD

    4.2 Matched Sets

    4.3 Finite Area Contacts

    4.4 MinCD to Semi-MinCD Conversion

    • 1. Conversion of Fig. 2.1
    • 2. Heavily Loaded Slide
    • 3. Lathe Carriage
    • 4. Bolted Foot
    • 5. Zero Looseness Hinge

    4.5 Useful RedCD

    • 1. Large, Distributed Load
    • 2. Necessary Deformation
    • 3. Varying Load Distribution

    4.6 RedCD Components

    • 1. V-Band Fastener
    • 2. Retaining Rings
    • 3. Screw Threads
    • 4. "Piano Hinge"
    • 5. Flanged Joint

      4.7 Self Improving RedCD

      • 1. Wearing In
      • 2. Flat Lapping
      • 3. Parabolic Lapping
      • 4. Bearing Ball Lapping
      • 5. Circle Divider
      • 6. Lead Screw Lapping
      • 7. Hand Scraping
      • 8. Conical Bearings

      Part 2 Designing With Commercial Components

      Chapter 5 General Discussion

      5.1 Commercial vs. Special 5.1.1 Advantages of Commercial Components
      • 1. Development Costs
      • 2. Manufacturing Costs
      • 3. Experience
      • 4. Approvals

      5.1.2 Advantages of Your Own Design

      • 1. Suitability
      • 2. Costs
      • 3. Design Integration
      • 4. Independence
      • 5. Management Considerations
      • 6. Combining Ideas

      5.2 Approved Products 5.2.1 Your Company

      5.2.2 Other Organizations

      5.2.3 Your Customer

      5.3 Sources of Information 5.3.1 Your Program of Study

      • 1. Catalogs,
      • 2. Advertisements,
      • 3. Trade Shows.

      5.3.2 Purchasing Directories

      5.3.3 Manufacturers' Representatives and Salespeople

      5.4 Big Companies vs. Small Companies

      5.5 Components in This Book

      5.6 Organization of this Book Section

      5.7 CATEGORIES

      5.8 Breadth and Depth

      5.9 How to Use This Book

      Chapter 6 Rotary Motion

      6.1 Bearings 6.1.1 Rolling Bearings
      • 1. Ball Bearings,
      • 2. Roller Bearings.

      6.1.2 Bearing Housings

      6.1.3 Sliding Bearings

      • 1. Hydrodynamic Lubrication
      • 2. Hydrostatic Lubrication
      • 3. Dry

      6.1.4 Flexure Bearings

      6.2 Spindle assemblies

      6.3 Coupling Hubs to Shafts

      6.3.1 Interference Couplings

      6.3.2 Tapers and Collets

      6.4 Collars and Retaining Rings

      6.5 Shafting

      6.6 Clutches and Brakes

      6.6.1 Torque Generating Effects

      • 1. Dry Friction
      • 2. Lubricated Friction
      • 3. Hydrodynamic Forces
      • 4. Viscous Drag
      • 5. Magnetic Particle
      • 6. Eddy Current Drag
      • 7. Hysteresis Drag
      • 8. Positive Engagement
      • 9. Generators and Motors

      6.6.2 Control Effects

      • 1. Electricity
      • 2. Compressed Air
      • 3. Hydraulics
      • 4. Centrifugal Force
      • 5. Torque
      • 6. Angular Position
      • 7. Human

      6.7 Rotation Transmission

      6.7.1 Shaft Couplings

      6.7.2 Gears

      6.7.3 Gearless Speed Reducers

      6.7.4 Friction Drives

      • 1. V-Belts
      • 2. Multi-V-Belts
      • 3. Flat Belts
      • 4. Tooth Belts
      • 5. Round Belts

      6.7.5 Chains

      6.7.6 Indexing Drives

      6.7.7 Variable Speed Drives

      • 1. Variable Speed Motors
      • 2. Motor and Slip Clutch
      • 3. Friction
      • 4. V-Belt
      • 5. Hydraulic
      • 6. Gear Shift

      Chapter 7 Linear Motion

      7.1 Bearings, Wheels, and Tracks

      7.1.1 Roller and Track Matched Sets

      • 1. Round Tracks
      • 2. Non-Round Tracks
      • 3. Roller Bearing Systems
      7.1.2 Complete Matched Sets

      7.2 Wheels

      7.2.1 Wheels For Flat Paths

      7.3 Wheel Steering

      7.4 Wheel and Track Matched Sets

      7.5 Hydrostatic Sliding Bearings

      7.6 Lead Screws and Nuts

      7.7 Belts, Chains, and Ropes

      Chapter 8 Power

      8.1 Available Forms of Power

      8.2 Power Sources

      8.2.1 Electricity

      • 1. Motors
      • 2. Other Electric Actuators
      • 3. Heaters
      • 4. Electrical Controls
      • 5. Wiring Devices.

      8.2.2 Hydraulics

      • 1. Cylinders
      • 2. Motors
      • 3. Control Devices
      • 4. Plumbing
      • 8.2.3 Pneumatics
      • 8.2.4 Explosives
      • 8.2.5 Springs
      • 8.2.6 Flywheels
      • 8.2.7 Heat Engines
      • 8.2.8 Fuel Burning
      • 8.2.9 Human Power

      Chapter 9 Other Components

      • 9.1 Semi-Finished Materials
      • 9.2 Structural Systems
      • 9.3 Enclosures
      • 9.4 Machine Modules
      • 9.5 Fasteners
      9.5.1 Threaded Fasteners
      • 1. Data and Specifications
      • 2. Threaded Inserts
      • 3. Sheet Metal Nuts
      • 4. Other Forms

      9.5.2 Thread Locking

      • 1. Lockwashers
      • 2. Locknuts
      • 3. Lockwire
      • 4. Castellated Nuts
      • 5. Insert Nuts
      • 6. Insert Bolts
      • 7. Deformed Nuts
      • 8. Adhesives

      9.5.3 Non-Threaded Fasteners

      • 1. Rivet
      • 2. Other Fasteners
      • 3. Latches

      9.6 Vibration and Shock Absorbers

      • 9.6.1 "Shock Mounts"
      • 9.6.2 Shock Absorbers
      • 9.7 Springs
      • 9.8 Lubrication
      • 9.9 Seals and Guards
      • 9.10 Sensors and Displays
      9.10.1 Parameters

      9.11 Sequence Controls

      • 9.11.1 Timers
      • 9.11.2 Drum Controllers
      • 9.11.3 Relay Circuits
      • 9.11.4 Programmable Controllers (PLC)
      • 9.11.5 Computers
      • 9.11.6 Non-Electrical Controllers
      • 9.12 Tooling Components
      • 9.13 Permanent Magnets
      • 9.14 Lamps
      • 9.15 Nameplates
      • 9.16 Pumps and Blowers
      • 9.17 Miscellaneous

      Exercises in Design With Commercial Components

      Part 3 Topics in Design Engineering

      Chapter 10 Designing With Uncommon Manufacturing

      10.1 List of Processes

      Chapter 11 Manufacturing Engineering

      11.1 What Is Manufacturing Engineering?
      • 1. Standard Machines
      • 2. Special Machines for Sale
      • 3. Special Machines For Your Company
      • 4. R&D
      • 5. Tool Design
      • 6. Planning and Scheduling
      • 7. Maintenance

      11.2 Suggestions

      • 1. Risk Responsibility
      • 2. Technician Work, Engineering Work
      • 3. Motivation
      • 4. Offices
      • 5. Education

      Chapter 12 Optimum Level of Mechanization and Automation

      12.1 Classification
      • 12.1.1 Fully Automatic
      • 12.1.2 Powered Machines With Human Control
      • 12.1.3 Combination Human and Automatic
      • 12.1.4 Human Work With Power Tools
      • 12.1.5 Human Workers With Special Hand Tools
      • 12.2 Assembly Kits
      • 12.3 The Benefits of Automation
      • 12.4 Justifying the Cost of Automation
      • 12.5 Policy Questions

      Chapter 13 Robots

      • 13.1 History and Myth
      • 13.2 Robot Reality
      13.2.1 End Effectors
      • 1. Fabricating Tools
      • 2. Material Handling Tools
      • 3. Sensors
      • 4. Military Components
      • 5. Quick Change Grippers
      13.3 Robot Control
      • 13.3.1 Point To Point Robots
      • 13.3.2 Continuous Path Robots
      • 13.3.3 Human Remote Control
      13.4 Robot Mechanisms 13.4.1 Linear vs. Rotary
      • 1. Errors
      • 2. Flexibility
      • 3. Inertia
      • 4. Geometry Computation
      13.5 Cartesian Robots
      • 1. Accuracy
      • 2. Flexibility
      • 3. Ineria
      • 4. Position Computation
      • 5. Control
      • 6. Modularity
      • 7. Branching
      • 8. System Configuration

      13.6 Safety

      13.7 Cartesian Robot Configurations

      • 1. Bridge Crane
      • 2. Half Bridge
      • 3. Vertical Bridge

      • 13.8 Programming
      • 13.9 Accuracy vs. Repeatability
      • 13.10 Conversion From Task To Task
      • 13.11 Variation Within Task
      • 13.12 Money
      • 13.13 Humans vs. Robots
      • 1. Task To Task Conversion
      • 2. Capital Cost
      • 3. Multiple Tasks
      • 4. Mobility
      • 5. Expanded Scope
      • 6. Bad Part Rejection
      • 7. Task Modification
      • 8. Dexterity
      • 9. Speed
      • 10. Maintenance
      • 11. Technology

      13.14 Disadvantages of Human Workers

      • 1. Work Uniformity
      • 2. Unions
      • 3. Fatigue
      • 4. Conflicts
      • 5. Absenteeism
      • 6. Injuries
      • 13.15 Economic Justification
      • 13.16 Task Size and Force
      • 13.17 Abuse Resistance
      • 13.18 The Future

      Chapter 14 Grippers

      14.1 Methods of Gripping
      • 14.1.1 Friction
      • 14.1.2 Vacuum
      • 14.1.3 Electromagnets
      • 14.1.4 Special Gripping Devices
      • 14.2 Environmental Limitations
      • 14.3 Gripper Actuation
      • 14.4 Misalignment
      • 14.4.1 Passive Self-Alignment
      • 14.4.2 Active Self-Alignment

      Chapter 15 Selecting Power Forms

      15.1 Forms of Power
      • 15.1.1 Electricity
      • 15.1.2 Pneumatics
      • 15.1.3 Hydraulics

      1. Force, 2. Power, 3. Incompressibility.

      • 15.1.4 Vacuum
      • 15.1.5 Combustion Engines
      • 15.1.6 Explosives
      • 15.1.7 Human Muscle
      • 15.1.8 Heat
      • 15.1.9 Sunlight
      • 15.1.10 Wind
      • 15.1.11 Gravity
      • 15.1.12 Elasticity
      • 15.1.13 Inertia
      • 15.1.14 Utility Water
      • 15.1.15 Nuclear
      • Chapter 16 Backlash

      • Chapter 17 Hype

      • Chapter 18 Product Deterioration

      • 18.1 Spontaneous Deterioration
      • 18.2 Attacks During Shipment
      • 18.3 Environmental Attacks
      • 18.4 Wear
      • 18.5 Abuse
      • 18.6 Design and Manufacturing Errors
      • 18.7 Modification by User
      • 18.8 What Can You Do About It?

      Chapter 19 Electrical and Mechanical Technologies: Competition and Cooperation

      19.1 History

      19.2 Electrical Takeovers

      • 1. Motors
      • 2. Variable Speed Motors
      • 3. Instrumentation and Control
      • 4.Programming
      • 5. Computing

      19.3 Mechanical Instru

 

Lawrence Kamm
Licensed Prof. Engr.
B.S. and M.S. in Electrical Engineering
"I calls 'em as I sees 'em"
phone: 619-224-3494
fax: 619-224-3495
LJKAMM@LJKAMM.COM
1515 Chatsworth Blvd.
San Diego CA 92107